In a rewritable non-volatile semiconductor memory device that is highly integrated, a word line is used in a manner that is shared among a plurality of memory cells. The word line is driven by a driver that is integrated. When a length of the word line changes, a resistance value or parasitic capacitance of the word line changes. For this reason, a voltage waveform that varies with a position thereof is applied to a memory cell.
A difference in a waveform of a voltage that is applied to the memory cell at the time of data programming causes dispersion in an amount of shift of a threshold voltage of the memory cell, and has an influence on stability of operation of a product.
In recent years, progress in high integration has been made, and a three-dimensionally structured NAND memory has progressed to a mainstream memory. Thus, dispersion in a threshold voltage in the direction of stacking memory cells has had an influence on stability of operation of a product as well.